Baking Alaska’s glaciers

Alaska’s glaciers have been disappearing at an alarming rate, producing a torrent of melt water that contributes to sea-level rise. However, scientists are unsure whether most of the ice loss has happened through slow surface melting, or through the dramatic collapse of floating tidewater glaciers like the Columbia Glacier (below). Somewhat surprisingly, a new study shows that tidewater glaciers produce a relatively small proportion of Alaska’s meltwater. Listen to my podcast for Scientific American’s 60-Second Science to learn why that’s not necessarily good news.

The Columbia Glacier in Southeast Alaska is a tidewater glacier that retreated 12 miles in the last 25 years, accounting for 1% of the global sea-level rise budget all on its own. (Credit: NASA/USGS)